New research from the Centers for Disease Control and Prevention (CDC) reveals an additional two million kids have attention attention-deficit/hyperactivity disorder compared to stats collected nearly a decade earlier.

One million more kids are also taking medications to treat their ADHD, according to the new data collected from 2011-2012.

A government study of young adults found a sharp increase in ER visits due to stimulant drug use, most involving people taking ADHD medication.

“The number of U.S. households impacted by childhood diagnoses of ADHD is growing,” Susanna Visser, an epidemiologist with the CDC’s National Center on Birth Defects and Developmental Disabilities, said in a press release. “When children diagnosed with ADHD receive proper treatment, they have the best chance of thriving at home, doing well at school, and making and keeping friends.”

ADHD is considered a neurobehavioral disorder and it often lasts into adulthood. It is characterized by problems paying attention and controlling impulses, daydreaming, being overly active with squirming or fidgeting, and having difficulty getting along with others.

For the study, researchers compared data sets collected from the National Survey of Children’s Health to calculate the number of U.S. children and adolescents between the ages of 4 and 17 that received an ADHD diagnosis from a doctor.

They found for 2011-2012, 6.3 million children received an ADHD diagnosis, which represented a 42 percent rise over 2003-2004 rates. That means about 11 percent of U.S. kids and adolescents currently are diagnosed with ADHD.

Recent studies have also found rises in ADHD diagnosis rates over the past decade, ranging from 24 percent to 53 percent.

As for medication, more than 3.5 million of America’s youth are taking ADHD drugs, a 28 percent rise over rates collected in 2007-2008.

Federal health officials felt not nearly enough kids with ADHD were receiving treatment: Almost 18 percent of the kids did not receive mental health counseling or medication in 2011-2012. Of them, one-third were reported to have moderate or severe ADHD.

"This finding raises concerns about whether these children and their families are receiving needed services," said Dr. Michael Lu, senior administrator for the government’s Health Resources and Service Administration, said in a written statement.

About half of the children were diagnosed by age 6, but about half of those with severe cases of ADHD received a diagnosis around 4 years old.

The new findings were published Nov. 22 in the Journal of the American Academy of Child and Adolescent Psychiatry.

Online Public Information File

Viewers with disabilities can get assistance accessing this station's FCC Public Inspection File by contacting the station with the information listed below. Questions or concerns relating to the accessibility of the FCC's online public file system should be directed to the FCC at 888-225-5322, 888-835-5322 (TTY), or fccinfo@fcc.gov.